Accumulative stone throwing chimpanzees like tree species with a resonating timbre

An international collaboration of researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, the CNRS Lab for Perception, Representations, Image, Sound and Music (PRISM) and the Lab for Mechanical Acoustics (LMA) in Marseille, France, has discovered that one of our closest living relatives is attuned to the sound properties of external objects in their natural environment, namely the wood of different tree species. Using a unique field experiment, the researchers found that chimpanzees living in Boé, Guinea-Bissau, use tree species for accumulative stone throwing behaviour that produce more resonant sounds when hit with rocks compared to other species available in the environment.

How did the almost 6000 languages of the world come into being? Researchers from the Leipzig Research Centre for Early Childhood Development at Leipzig University and the Max Planck Institute for Evolutionary Anthropology have tried to simulate the process of developing a new communication system in an experiment – with surprising results: even preschool children can spontaneously develop communication systems that exhibit core properties of natural language.

Monkeys cooperatively share information about the presence of snakes with group members

Humans are often faced with the choice of investing in the greater good or being selfish and letting others do the work. Animals that live in groups often encounter threats, and informing others could potentially save lives. Researcher of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, show that wild sooty mangabeys, when facing dangerous vipers, do not just call out of fear or to warn their family, but will call when the information about the threat might otherwise not reach all group members.

The first comprehensive study of the human ability to recognize the facial expressions of dogs suggests this ability is mainly acquired through age and experience and is not an evolutionarily selected trait, and in adults is better in those growing up in dog-positive cultural contexts. In a recent study published in Scientific Reports, a team of German and British researchers assessed how experience with dogs affects humans’ ability to recognize dog emotions. Participants who grew up in a cultural context with a dog-friendly attitude were more proficient at recognizing dog emotions. This suggests that the ability to recognize dogs’ expressions is learned through age and experience and is not an evolutionary adaptation.

In order to investigate evolutionary questions, scientists require the largest and most versatile samples possible. If those samples are not available in one place, research institutions can support each other. This is the rationale behind ManyPrimates, a project that aims to establish a culture of global collaboration in primate cognition research. It was set up by researchers from the Leipzig Research Center for Early Childhood Development (LFE) at Leipzig University, the Max Planck Institute for Evolutionary Anthropology, and Zoo Leipzig.

Considered an oil palm pest, macaques can in fact diminish a more severe pest: rats

In Malaysia, wild pig-tailed macaques do not have the best reputation and are even considered a crop pest. Contrary to this, they actually feed on rats, the major oil palm pest, and can provide an important ecosystem service as biological pest control agent. This was found by a team of researchers from Universiti Sains Malaysia (USM), the German Centre for Integrative Biodiversity Research (iDiv), Leipzig University (UL) and the Max Planck Institute for Evolutionary Anthropology (MPI-EVA). Their research investigates the costs and benefits of macaques foraging in oil palm plantations.

Cell atlas of great ape forebrain development illuminates dynamic gene-regulatory features that are unique to humans

Researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, Institute of Molecular and Clinical Ophthalmology Basel, and ETH Zurich, Switzerland, present new insights into the development of the human brain and differences in this process compared to other great apes. The study reveals features of brain development that are unique to humans, and outlines how these processes have diverged from those in other primates.

Scientists from the University of Leipzig and the Max Planck Institute for Evolutionary Anthropology found that male common marmosets are able to detect the fertile phase of females based on changes in their body odor. Using a combination of chemical analyses and a behavioral test they found that female common marmosets release various substances that produce a specific smell during their fertile phase and that males can perceive these olfactory changes.

Female gorillas must balance the reproductive costs of staying with or leaving an older male

When a gorilla group’s silverback is close to the end of his reproductive years, females face a dilemma: Should they stay with him until he dies or leave him for another male? A team of researchers from the Max Planck Institute of Evolutionary Anthropology has now found that both strategies bear its costs: females face reproductive costs of staying with an older male as well as costs when they transfer to a new silverback.

New insights help to explain why same-sex sexual interactions are so important for female bonobos

To understand the origins of human sociality studying the social dynamics of our closest relatives, chimpanzees and bonobos, is important. Using behavioral and hormonal data from a habituated bonobo community at the long-term LuiKotale field site in the Democratic Republic of Congo researchers from the Max Planck Institute for Evolutionary Anthropology, Harvard University and the Leibniz Institute for Farm Animal Biology have now shown that same-sex sexual behavior in female bonobos increases friendly social interactions, including cooperation.

Australopithecus anamensis is the earliest-known species of Australopithecus and widely accepted as the progenitor of “Lucy’s” species, Australopithecus afarensis. Until now, A. anamensis was known mainly from jaws and teeth. Yohannes Haile-Selassie of the Cleveland Museum of Natural History, Stephanie Melillo of the Max Planck Institute for Evolutionary Anthropology and their colleagues have discovered the first cranium of A. anamensis at the paleontological site of Woranso-Mille, in the Afar Region of Ethiopia.

How does the playing behaviour of children influence their prosocial behaviour?

This is the question scientists at the Leipzig Research Centre for Early Childhood Development (LFE) at the University of Leipzig and the Max Planck Institute for Evolutionary Anthropology in Leipzig have researched. It turned out that cooperative games encouraged the willingness to share with other children. The researchers have now published their new findings in the specialist journal “PLoS ONE”.

Sometimes recording what animals do not do or fail to find can lead to revealing insights into their expectations, and thus cognition

Studying cognition in the wild is a challenge. Field researchers and their study animals face many factors that can easily interfere with their variables of interest and that many say are “impossible” to control for. A novel observational approach for field research developed by Karline Janmaat at the Max Planck Institute for Evolutionary Anthropology can now guide young scholars, who want to study cognition in the field before this opportunity disappears.

Long-term study of Amazonian community shows the interconnectedness of cooperation and status hierarchy

While other animals tend to gain status through aggression, humans are typically averse to allowing such dominant individuals to achieve high status. Instead, those highest in social status are often those who demonstrate the most value to others. Researchers have now shown that cooperation between individuals can be driven by opportunities to acquire status over others and that decisions with whom to cooperate are often based on who has more or less status.

A long-term study of western gorillas in Gabon has revealed an unexpected behaviour – they use their teeth to crack open and eat nuts

Scientists from the Max Planck Institute for Evolutionary Anthropology and Washington University in St. Louis have observed a population of western lowland gorillas in Loango National Park, Gabon using their teeth to crack open the woody shells of Coula edulis nuts. The researchers combined direct feeding observations and mechanical tests of seed casings to show that gorillas may be taxing their teeth to their upper limits, year after year, to access this energy rich food source.

Travel linearity increases in humans when they travel in increasingly large groups, while chimpanzees travel more goal-directed when they are on their own

How do human-unique ranging styles, like large home range and trail use, influence the way we travel to our goals? Researchers from the Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany, investigated spatial movement patterns of the Mbendjele BaYaka people and Taï chimpanzees. Human foragers and chimpanzees travelled in similarly straight lines towards goals, but they showed clearly different patterns in how they change linearity and speed depending on group size and familiarity with an area.

Human foragers of both sexes use the sun for finding direction from a very young age

How do human foragers find food or the way home in rainforests, where heavy vegetation limits visibility, without a map, compass, or smartphone? Researchers at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, show that rainforest-dwelling Mbendjele BaYaka people from the Republic of Congo point to out-of-sight targets with high precision. Pointing accuracy was equally good in men and women; children’s performance improved when the sun was clearly visible in the sky.

Contrary to humans, chimpanzees did not use search strategies to facilitate their task

Working memory is central to our mental lives; we use it to add up the cost of our shopping or to remember the beginning of this sentence at its end. Some scientists argue it is particularly developed in humans, but how do chimpanzees, one of our closest relatives, compare? Researchers from the University of St Andrews, the Max Planck Institute for Evolutionary Anthropology, and the University of Veterinary Medicine Vienna set out to answer this question.

Flies carrying deadly pathogens form long-term associations with monkeys and apes following them through the rainforest

People the world over have a good sense that flies are filthy and that we do not want them landing on our food during our summer picnics. Research has justified that disgust, showing that flies associated with humans and their livestock spread a diversity of pathogens. In a collaboration with Roman Wittig of the Max Planck Institute for Evolutionary Anthropology and the Taï Chimpanzee Project, a research team led by Fabian Leendertz at the Robert Koch Institute in Germany has now shown that such fly associations also exist in highly mobile non-human primate groups as they move kilometers every day through the rainforest.

From African golden cats to zebra duikers, Chimp&See lets you get up close and personal with African wildlife

Have you ever wondered what an elephant gets up to during a typical day? Or maybe what a baboon sounds like? What about the social circles of chimpanzees? If so, then good news – you’re not alone! Thousands of people from all walks of life have come together to form a community at Chimp&See, a citizen science project hosted by Zooniverse where members of the public can volunteer their time to watch, classify, and discuss camera trap videos taken from sites all across Africa as part of the Pan African Programme: The Cultured Chimpanzee (PanAf) from the Max Planck Institute for Evolutionary Anthropology.

Female mammals kill the offspring of their competitors when resources are scarce

The killing of rivals’ offspring represents a violent manifestation of competition, and a significant source of offspring mortality in some mammalian populations. Previous research on such infanticide has focused on males, but a new study by Dieter Lukas from the Max Planck Institute for Evolutionary Anthropology and Elise Huchard from the Institut des Sciences de l’Évolution, Montpellier shows that infanticide by females is also widespread across mammals and that females are likely to gain substantial benefits from it.

Study offers a possible answer on how our human ancestors may have met their nutritional needs of iodine in the Congo basin

Researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, have for the first time observed bonobos in the Congo basin searching for and eating iodine-rich aquatic plants in the swamps. Iodine is a critical nutrient for brain development and higher cognitive abilities. According to the research team, these observations may explain how the nutritional needs of prehistoric humans in the region were met.

Early ancestors of the last Neandertals lived in Europe already 120,000 years ago

Parts of the genomes of two around 120,000-year-old Neandertals from Germany and Belgium have been sequenced at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. The analyses of these sequences showed that the last Neandertals, who lived around 40,000 years ago, trace at least part of their ancestry back to these European Neandertals that lived around 80,000 years earlier. The 120,000-year-old Neandertal from Germany, however, carried some ancestry that may originate from an isolated Neandertal population or from relatives of modern humans.

Mankind’s closest living relatives – chimpanzees – are disappearing from the earth, because their habitats are destroyed and they are being eaten into extinction

In May 2019, over 40 scientists met at a symposium in Leipzig, Germany, to talk about the wild chimpanzee populations that they have been studying for decades. The occasion was the 40th anniversary of a long-term research and conservation project on chimpanzees in the Taï National Park, Côte d’Ivoire.

Scientists discover the oldest systematically produced stone artifacts to date

A new archaeological site discovered by an international and local team of scientists working in Ethiopia shows that the origins of stone tool production are older than 2.58 million years ago. Previously, the oldest evidence for systematic stone tool production and use was 2.58 to 2.55 million years ago. A group of archaeologists and anthropologists led by David Braun from George Washington University and the Max Planck Institute for Evolutionary Anthropology suggests that stone tools may have been invented many times in many ways before becoming an essential part of the human lineage.

An in situ exhibition at the Max Planck Institute for Evolutionary Anthropology in Leipzig

In Emanuel Mathias' artistic research work “On the Margins of the Field”, the observing field primatologist becomes him- or herself the observed subject of investigation. For this project, Mathias collaborated with about 20 researchers from the Department of Primatology at the Max Planck Institute for Evolutionary Anthropology, following the traces the researchers left behind from their observational field work in the form of recordings and written documentation. The exhibition is open for external visitors from May 29 to July 19, 2019, on weekdays from 8:00 a.m. to 6:00 p.m. (Deutscher Platz 6, Leipzig).

Wild chimpanzees eat tortoises after cracking them open against tree trunks

An international team of researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig and the University of Osnabrück, Germany, have observed wild chimpanzees in the Loango National Park, Gabon, eating tortoises. They describe the first observations of this potentially cultural behavior where chimpanzees hit tortoises against tree trunks until the tortoises’ shells break open and then feed on the meat.

Mothers’ presence influences the reproductive success of their adult sons

In many social animal species individuals share child-rearing duties, but new research from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, finds that bonobo mothers go the extra step and actually take action to ensure their sons will become fathers. This way bonobo mothers increase their sons’ chance of fatherhood three-fold.

So far Denisovans were only known from a small collection of fossil fragments from Denisova Cave in Siberia. A research team led by Fahu Chen from the Institute of Tibetan Plateau Research, CAS, Dongju Zhang from Lanzhou University and Jean-Jacques Hublin from the Max Planck Institute for Evolutionary Anthropology now describes a 160,000-year-old hominin mandible from Xiahe in China. Using ancient protein analysis the researchers found that the mandible’s owner belonged to a population that was closely related to the Denisovans from Siberia. This population occupied the Tibetan Plateau in the Middle Pleistocene and was adapted to this low-oxygen environment long before Homo sapiens arrived in the region.

By focusing on a group of organisms taxon-specific databases make a broad range of high-quality data accessible

We used data from the IUCN SSC A.P.E.S. database, to show the wealth of information that can be derived from a database that focuses on a specific group of organisms. For this study we focused on the western chimpanzee, a critically endangered subspecies of chimpanzees. Many taxon-specific databases already exist, but are largely underfunded. These databases are, however, in a unique position to fill the niche between local data collectors and global data bases to contribute to closing the large gaps in biodiversity data that still persist. More and more data on patterns and trends of biodiversity are becoming available. However, even though a lot of data have been and are being collected, they are often not accessible to researchers, decision-makers, planners and conservation practitioners.

DNA sequences from Indonesia and New Guinea reveal new branches of the Denisovan family tree

As they dispersed out of Africa anatomically modern humans interbred with their close relatives, the Neanderthals and Denisovans. An international research team examined DNA fragments passed down from these ancient hominins to modern people living in Island Southeast Asia and New Guinea. Their study suggests that the ancestry of Papuans includes not just one but two distinct Denisovan lineages, which had been separated from each other for hundreds of thousands of years. In fact, one of those Denisovan lineages is so different from the other that they might even be considered an entirely new group of archaic hominins.

Songbirds that work together with raising their young coordinate its attention and exchange itself intensively with each other

Cooperative breeding may facilitate the development of sophisticated communicative abilities such as intentionality and joint attention skills. Two new studies of researchers of the Max Planck Institute for Ornithology in Seewiesen, the Max Planck Institute for Evolutionary Anthropology in Leipzig and the University of Osnabrück provide the first evidence that a cooperatively breeding bird species (Arabian babblers) demonstrates distinct hallmarks of joint-attentional skills, which have been traditionally ascribed to humans only. This result also shows that an ape-like cognitive system is not a necessary pre-condition for joint-attention skills.

Male chimpanzees reduce aggression when social relationships in their group are unstable

An international team of researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, conducted behavioral observations and collected urine samples for cortisol analysis of male chimpanzees of the Taï National Park, Ivory Coast, during periods of intense male-male competition. They showed that all males had higher stress levels during periods of increased male-male competition while aggression rates were actually lower during this time. This may indicate that in times of social instability animals refrain from aggressive actions to avoid escalation of conflicts and to promote group cohesion.

Psychologist Daniel Haun is joining the Max Planck Institute for Evolutionary Anthropology (MPI-EVA) as new Director on 1 April 2019. He was most recently a Professor for Early Child Development and Culture at Leipzig University and the Director of the Leipzig Research Center for Early Child Development. Haun is interested in the ways in which human cognition adapts to, shapes and enables cultural diversity.

Visual artists Elmar Hermann and Emanuel Mathias are interested in the relationship between science and art, language and image. In their new exhibition they address simple principles of visual communication.

Yawning is contagious in both chimpanzees and humans, a possible proof that both are empathic being. Yawning is a reflexive-instinctive behavior that seems to be characteristic of all vertebrates. Yet its causes and purposes have not yet been completely identified. In addition to solely physiological causes, communicative purposes may play an important role, too. Within the context of the exhibition "Zzzz", large-format photographs of yawning humans and non-human primates are attached to window-panes at the MPI-EVA's Wolfgang Koehler Primate Research Center ("Pongoland") at the Zoo Leipzig. This exhibition is part of a larger exhibition called "buchstäblich" (engl. "literally") that takes place from March 21 to April 28, 2019.

African wild apes notice and often react to novel items in their environment

An international team of researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, analyzed video from remote camera-trap devices placed in ape-populated forests throughout Africa to see how wild apes would react to these unfamiliar objects. Responses varied by species, and even among individuals within the same species, but one thing was consistent throughout: the apes definitely noticed the cameras.

New research leads the way in validating a promising human brain model

The human brain is one of the most complex organs. Its complexity challenges our ability to study its structure and function. As a result, many brain-related diseases are not fully understood and adequate treatments are often lacking. Scientists from Max Planck Institute of Psychiatry (MPI) were able to model a developmental disorder called neuronal heterotopia which can lead to intellectual disability and epilepsy. They used a model of brain development called brain organoids where human cells organize themselves in the petri dish into brain-like structures. These brain organoids enabled the researchers to accurately recapitulate the disease in the lab. They discovered that the cells contained in the organoids, derived from individuals affected by the disease, had a different morphology and navigation system. In particular the scientists were able to find a full new set of molecular signatures that are unique in the diseased cells, giving them now potential ideas of how they can identify possible targets and strategies to develop therapy for patients. Barbara Treutlein from the MPI for Evolutionary Anthropology contributed to this study.

Chimpanzees are well known for their extraordinary diversity of behaviors, with some behaviors also exhibiting cultural variation. An international research team led by the Max Planck Institute for Evolutionary Anthropology and the German Centre for Integrative Biodiversity Research (iDiv) investigated whether chimpanzee behavioral diversity is reduced under high human impact. By comparing sets of chimpanzee behaviors across a large number of social groups exposed to different levels of human disturbance, the scientists found a reduction in behavioral diversity when human impact was high.

Increased dust loads result in decreased chewing efficiency in chimpanzees

Periodical dust loads on foods places dietary-physiological stress on the digestive system in chimpanzees. This is the conclusion reached by an international research team headed by scientists from the Max Planck Institute for Evolutionary Anthropology (MPI-EVA) in Leipzig. Their study implicates that extrinsic abrasive particles carried by dust-laden winds affect tooth wear and evolutionary fitness.

Different cultures, different habits and different behavioral patterns – this applies not only to humans but also to chimpanzees, one of our two closest living relatives. A team of researchers from the Max Planck Institute for Evolutionary Anthropology (MPI-EVA) in Leipzig, Germany, and The University of Warsaw in Poland now describes a new ‘behavioral realm’ of the Eastern chimpanzee (Pan troglodytes schweinfurthii) of the Bili-Uéré region in Northern DR Congo, based on the results of a 12-year study.

Isotope analyses performed on single amino acids in Neandertals’ collagen samples shed new light on their debated diet

A specific feature of modern humans seems to be their frequent fish consumption, which can be determined by nitrogen isotope analyses of bone or tooth collagen. An international research team, led by researchers from the Max Planck Institute for Evolutionary Anthropology, discovered two late Neandertals characterized by exceptionally high nitrogen isotope ratios, which would traditionally be interpreted as the signature of freshwater fish consumption. By studying the isotope ratios of single amino acids, they however demonstrated that instead of fish, the adult Neandertal had a diet relying on large herbivore mammals and that the other Neandertal was a breastfeeding baby whose mother was also a carnivore. According to isotope data, Neandertals seem to have had a very stable diet over time, including after the arrival of modern humans in Europe.

Orangutans make complex economic decisions about tool use depending on the current 'market' situation

Flexible tool use is closely associated to higher mental processes such as the ability to plan actions. Now a group of cognitive biologists and comparative psychologists from the University of Vienna, the University of St Andrews and the University of Veterinary Medicine Vienna that included Isabelle Laumer and Josep Call, has studied tool related decision-making in a non-human primate species – the orangutan. They found that the apes carefully weighed their options: eat an immediately available food reward or wait and use a tool to obtain a better reward instead? To do so the apes considered the details such as differences in quality between the two food rewards and the functionality of the available tools in order to obtain a high quality food reward, even when multidimensional task components had to be assessed simultaneously. The study was conducted in cooperation with the Max Planck Institute for Evolutionary Anthropology at the Zoo Leipzig in Germany.

Humans are considered to be superior tool users and uniquely able to teach skills to apprentices. However, a clear understanding of the differences between humans and other animal species has been limited by our difficulty to perform natural cross-species comparisons. A research team from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and from the University College London, UK, compared humans' and chimpanzees' learning to crack the same species of nuts as they forage for food in the African forest.

The language we speak affects the way we process, store and retrieve information

Memory plays a crucial role in our lives, and several studies have already investigated how we store and retrieve information under different conditions. Typically, stimuli presented at the beginning and at the end of a list are recalled better than stimuli from the middle. But are these findings universal and generalizable across languages and cultures? An international research team, led by Federica Amici from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, has recently investigated this question.

New studies reveal deep history of Denisovans and Neanderthals in southern Siberia

Denisova Cave is the only site in the world known to have been occupied by both Denisovans and Neanderthals at various times. Two new studies published in the journal Nature, now put a timeline on when the two groups of archaic humans (hominins) were present at the site and the environmental conditions they faced before going extinct. The studies identify the age of the earliest Denisovans and Neanderthals in Southern Siberia. One of the studies, was led by Dr Katerina Douka from the Max Planck Institute for the Science of Human History, while the other one was led by Zenobia Jacobs of the University of Wollongong in Australia.

Scientists can reconstruct the feeding behavior and habitats of extinct vertebrates

Plant phytolith and water content cause differing degrees of tooth enamel abrasion in vertebrates. This is the conclusion reached by an international research team headed by scientists from Johannes Gutenberg University Mainz (JGU). Featured online before print in the journal PNAS, their study has implications for how tooth wear in extinct animals is interpreted and how this information can be employed to reconstruct their dietary behavior and habitats. Ellen Schulz-Kornas of the Max Planck Institute for Evolutionary Anthropology in Leipzig contributed to this research.